CSS Box-sizing: border-box vs content-box
Content box
width: 300px
10+5+
300
+5+10 px = 330 px
30 px
Border box
width: 300px
10+5+270+5+10 px =
300
px
Default box
width: 300px
10+5+270+5+10 px =
300
px
just a test